Hi all, after some work I was able to extract a reproducible case:
This is the code:
#include <ostream>
extern std::ostream* the_dout;
namespace Debug
{
bool IsEnabled();
}
class MyClass
{
MyClass();
~MyClass();
int value;
};
MyClass:: MyClass() : value(0)
{
if (Debug::IsEnabled()) (*the_dout) << value << std::endl;
}
MyClass::~MyClass()
{
Debug::IsEnabled() && (*the_dout) << value << std::endl;
}
This is the command line:
g++ -c -fnon-call-exceptions -Wmaybe-uninitialized -O2 gcc10bug.cpp
And this is the error:
gcc10bug.cpp: In destructor 'MyClass::~MyClass()':
gcc10bug.cpp:24:56: warning: 'removed_return.24' may be used uninitialized in this function [-Wmaybe-uninitialized]
24 | Debug::IsEnabled() && (*the_dout) << value << std::endl;
| ^~~~
A few notes:
1. the ^~~~ is pointing at endl
2. the almost similar code in the constructor does not error out
2. there is no error if -fnon-call-exceptions is removed
Nick
On Wednesday, January 6, 2021, 11:35:01 AM PST, Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> wrote:
On Wed, Jan 06, 2021 at 06:25:32PM +0000, Nick Savoiu via Gcc-help wrote:
> Hi Martin, the program crashes, not GCC.
>
> My code does not contain any 'removed_return'. I suspect that it's a GCC thing so it would probably not appear in a -E output.
It's an artificial name GCC makes up (in IPA)
Segher
